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GPS广播星历的误差分析 被引量:7
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作者 张飞舟 程鹏 +1 位作者 杨泽民 赵利军 《计算机测量与控制》 北大核心 2013年第1期155-156,167,共3页
地面控制段和GPS卫星性能共同决定广播星历的质量,从而决定了卫星轨道的精度和卫星钟质量;由于新型卫星的发射使得卫星性能进一步提高,同时相关机构采取了一系列措施来提高地面观测质量,GPS广播星历的精度持续提高;文章通过分析GPS卫星2... 地面控制段和GPS卫星性能共同决定广播星历的质量,从而决定了卫星轨道的精度和卫星钟质量;由于新型卫星的发射使得卫星性能进一步提高,同时相关机构采取了一系列措施来提高地面观测质量,GPS广播星历的精度持续提高;文章通过分析GPS卫星2011年的广播星历误差情况与历史精度经过作比较,对比结果表明,GPS的广播星历精度较以前有了进一步的提高。 展开更多
关键词 广播星历 精密星历 SISRE 卫星钟钟
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Research Progress of Molecular Clock 被引量:2
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作者 龙承星 张波 马绍宾 《Agricultural Science & Technology》 CAS 2012年第12期2496-2498,2553,共4页
In the paper, related research and progress of molecular clock hypothesis were summarized, including definition of molecular clock, supporting proofs, contro- versy, significance and perfection, application and accomp... In the paper, related research and progress of molecular clock hypothesis were summarized, including definition of molecular clock, supporting proofs, contro- versy, significance and perfection, application and accompanying challenges. 展开更多
关键词 Molecular clock Molecular clock hypothesis Slowing-down of evolution Rate of molecular evolution
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DESIGN OF TWO-PHASE SINUSOIDAL POWER CLOCK AND CLOCKED TRANSMISSION GATE ADIABATIC LOGIC CIRCUIT 被引量:5
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作者 Wang Pengjun Yu Junjun 《Journal of Electronics(China)》 2007年第2期225-231,共7页
First the research is conducted on the design of the two-phase sinusoidal power clock generator in this paper. Then the design of the new adiabatic logic circuit adopting the two-phase sinusoidal power clocks--Clocked... First the research is conducted on the design of the two-phase sinusoidal power clock generator in this paper. Then the design of the new adiabatic logic circuit adopting the two-phase sinusoidal power clocks--Clocked Transmission Gate Adiabatic Logic (CTGAL) circuit is presented. This circuit makes use of the clocked transmission gates to sample the input signals, then the output loads are charged and discharged in a fully adiabatic manner by using bootstrapped N-Channel Metal Oxide Semiconductor (NMOS) and Complementary Metal Oxide Semiconductor (CMOS) latch structure. Finally, with the parameters of Taiwan Semiconductor Manufacturing Company (TSMC) 0.25um CMOS device, the transient energy consumption of CTGAL, Bootstrap Charge-Recovery Logic (BCRL) and Pass-transistor Adiabatic Logic (PAL) including their clock generators is simulated. The simulation result indicates that CTGAL circuit has the characteristic of remarkably low energy consumption. 展开更多
关键词 Circuit design Two-phase sinusoidal power clock Clock generator Clocked Transmission Gate Adiabatic Logic (CTGAL) circuit
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因声求义——《黄帝内经太素》重言词例释三则 被引量:1
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作者 张亭立 《中医教育》 2009年第2期50-51,共2页
重言词为由单音节或双音节字重叠构成的合成复音词,多用于描物摹状,是古汉语中的常见语言现象。古医籍中的重言词由于存在大量的俗写变体,如运用一般的重言词字面求解方法,往往容易造成望文生义、割裂医理的现象。以唐杨上善《黄帝内经... 重言词为由单音节或双音节字重叠构成的合成复音词,多用于描物摹状,是古汉语中的常见语言现象。古医籍中的重言词由于存在大量的俗写变体,如运用一般的重言词字面求解方法,往往容易造成望文生义、割裂医理的现象。以唐杨上善《黄帝内经太素》中的三则重言词为例,因声求义,通过寻找恰当的音同音近字,求得确切的解释,务求医理文理两相合宜。 展开更多
关键词 黄帝内经太素 重言词 因声求义 钟钟 济济 询询
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The genetic equidistance result:misreading by the molecular clock and neutral theory and reinterpretation nearly half of a century later 被引量:2
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作者 HU TaoBo LONG MengPing +3 位作者 YUAN DeJian ZHU ZhuBing HUANG YiMin HUANG Shi 《Science China(Life Sciences)》 SCIE CAS 2013年第3期254-261,共8页
In 1963,Margoliash discovered the unexpected genetic equidistance result after comparing cytochrome c sequences from different species.This finding,together with the hemoglobin analyses of Zuckerkandl and Pauling in 1... In 1963,Margoliash discovered the unexpected genetic equidistance result after comparing cytochrome c sequences from different species.This finding,together with the hemoglobin analyses of Zuckerkandl and Pauling in 1962,directly inspired the ad hoc molecular clock hypothesis.Unfortunately,however,many biologists have since mistakenly viewed the molecular clock as a genuine reality,which in turn inspired Kimura,King,and Jukes to propose the neutral theory of molecular evolution.Many years of studies have found numerous contradictions to the theory,and few today believe in a universal constant clock.What is being neglected,however,is that the failure of the molecular clock hypothesis has left the original equidistance result an unsolved mystery.In recent years,we fortuitously rediscovered the equidistance result,which remains unknown to nearly all researchers.Incorporating the proven virtues of existing evolutionary theories and introducing the novel concept of maximum genetic diversity,we proposed a more complete hypothesis of evolutionary genetics and reinterpreted the equidistance result and other major evolutionary phenomena.The hypothesis may rewrite molecular phylogeny and population genetics and solve major biomedical problems that challenge the existing framework of evolutionary biology. 展开更多
关键词 genetic equidistance overlap feature evolution molecular clock neutral theory maximum genetic diversity hypothesis MICROEVOLUTION MACROEVOLUTION
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